• 제목/요약/키워드: core stability

검색결과 657건 처리시간 0.026초

체간 재활을 위한 4-DOF 로봇의 설계 및 분석에 관한 연구 (Study on the Design and Analysis of a 4-DOF Robot for Trunk Rehabilitation)

  • 에이자드 아믈;표상훈;이건협;류성기;윤정원
    • 한국기계가공학회지
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    • 제19권7호
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    • pp.41-51
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    • 2020
  • This paper presents the development of a robotic system for rehabilitation of the trunk's ability to maintain postural control under different balance conditions. The system, developed with extensive input from rehabilitation and biomedical engineering experts, consists of a seat mounted on a robotic mechanism capable of moving it with four degrees of freedom (3 rotational and 1 translational). The seat surface has built in instrumentation to gauge the movements of the user's center of pressure (COP) and it can be moved either to track the movements of the COP or according to operator given commands. The system allows two types of leg support. A ground mounted footrest allows participation of legs in postural control while a seat connected footrest constrains the leg movement and limits their involvement in postural control. The design evolution over several prototypes is presented and computer aided structural analysis is used to determine the feasibility of the designed components. The system is pilot tested by a stroke patient and is determined to have potential for use as a trunk rehabilitation tool. Future works involve more detailed studies to evaluate the effects of using this system and to determine its efficacy as a rehabilitation tool.

코어강화를 동반한 시각적 되먹임 훈련이 뇌졸중 환자의 협응력, 균형과 보행능력에 미치는 영향 (Effect of Visual Feedback Training of Core Strength on Coordination, Balance and Walking Ability of Stroke Patients)

  • 윤삼원;손호희
    • 대한물리의학회지
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    • 제15권4호
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    • pp.145-153
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    • 2020
  • PURPOSE: This study compares the effects of HUBER rehabilitation and general rehabilitation treatment on the coordination, balance, and walking ability of stroke patients. METHODS: This study enrolled 38 randomized stroke patients, and data was collected for 6 weeks. All participants were randomly assigned to either the experimental group (n = 19) or control group (n = 19). The experimental group were administered Huber rehabilitation and general rehabilitation treatment. The control group was given only general rehabilitation treatment. Both treatments were conducted for 30 minutes during each training session, 3 training sessions per week, for 6 weeks. The coordination, balance, and walking ability were evaluated before and after the intervention, to compare the intergroup and intragroup changes. RESULTS: Change in the right LOS (limit of stability) (p < .001) and forward LOS (p < .02) following intervention were significantly greater in the experimental group than in the control group, but no significant group difference was observed between left LOS (p > .1) and backward LOS (p > .2). Alterations in coordination (p < .02) and TUG (p <. 05) were significantly greater after intervention in the experimental group than in the control group. CONCLUSION: These findings suggest that HUBER rehabilitation is effective in improving the coordination, balance, and walking ability in stroke patients. To strengthen and validate the results of this study, future studies related to HUBER rehabilitation are required.

RNAi Suppression of RPN12a Decreases the Expression of Type-A ARRs, Negative Regulators of Cytokinin Signaling Pathway, in Arabidopsis

  • Ryu, Moon Young;Cho, Seok Keun;Kim, Woo Taek
    • Molecules and Cells
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    • 제28권4호
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    • pp.375-382
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    • 2009
  • The 26S proteasome is a 2-MDa complex with a central role in protein turn over. The 26S proteasome is comprised of one 20S core particle and two 19S regulatory particles (RPs). The RPN12a protein, a non-ATPase subunit of the 19S RP, was previously shown to be involved in cytokinin signaling in Arabidopsis. To further investigate cellular roles of RPN12a, RNAi transgenic plants of RPN12a were constructed. As expected, the 35S:RNAi-RPN12a plants showed cytokinin signaling defective phenotypes, including abnormal formation of leaves and inflorescences. Furthermore, RNAi knock-down transgenic plants exhibited additional unique phenotypes, including concave and heart-shape cotyledons, triple cotyledons, irregular and clustered guard cells, and defects in phyllotaxy, all of which are typical for defective cytokinin signaling. We next examined the mRNA level of cytokinin signaling components, including type-A ARRs, type-B ARRs, and CRFs. The expression of type-A ARRs, encoding negative regulators of cytokinin signaling, was markedly reduced in 35S:RNAi-RPN12a transgenic plants relative to that in wild type plants, while type-B ARRs and CRFs were unaffected. Our results also indicate that in vivo stability of the ARR5 protein, a negative regulator of cytokinin signaling, is mediated by the 26S proteasome complex. These results suggest that RPN12a participates in feedback inhibitory mechanism of cytokinin signaling through modulation of the abundance of ARR5 protein in Arabidopsis.

2011년 2월 11~12일 부산 근해에서 발달한 극저기압에 대한 사례연구 (A Case Study on the Polar Low Developed over the Sea Near Busan on 11~12 February 2011)

  • 이재규;김해민;김유진
    • 대기
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    • 제26권2호
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    • pp.301-319
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    • 2016
  • The evolutionary process of the polar low, which caused the heavy snowfall in the East Coast area on 11~12 February 2011, was investigated to describe in detail using synoptic weather charts, satellite imageries, and ERA (European Centre for Medium-Range Weather Forecasts Re-Analysis) -Interim reanalysis data. It was revealed that 1) the polar low was generated over the sea near Busan where a large cyclonic shear in the inverted trough branched from the parent low existed, 2) during the developing and mature stages, there was a convectively unstable region in the lower layer around the polar low and its south side, 3) the polar low was developed in the region where the static stability in the 500~850 hPa layer was the lowest, 4) the result from the budget analysis of the vorticity equation indicated that the increase in the vorticity at the lower atmosphere, where the polar low was located, was dominated mainly by the stretching term, 5) the warm core structure of the polar low was identified in the surface-700 hPa layer during the mature stage, 6) there was a close inverse relationship between a development of the polar low and the height of the dynamic tropopause over the polar low, and 7) for generation and development of the polar low, large-scale circulation systems, such as upper cold low and its combined short wave trough, major low (parent low), and polar air outbreak, should be presented, indicating that the polar low has the nature of the baroclinic disturbance.

Histological comparison of different compressive forces on particulate grafts during alveolar ridge preservation: a prospective proof-of-concept study

  • Lee, Sung-Jo;Kang, Dae-Young;Cho, In-Woo;Shin, Hyun-Seung;Shin, Seung-Il;Fischer, Kai R.;Park, Jung-Chul
    • Journal of Periodontal and Implant Science
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    • 제50권3호
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    • pp.197-206
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    • 2020
  • Purpose: The aim of this study was to determine the impact of different compressive forces on deproteinized bovine bone mineral (DBBM) particles covered by native bilayer collagen membrane (NBCM) during alveolar ridge preservation (ARP) in the molar area, and to identify any histomorphometric and clinical differences according to the compressive force applied. Methods: Sockets were filled with DBBM after tooth extraction, and different compressive forces (30 N and 5 N, respectively) were applied to the graft material in the test (30 N) and control (5 N) groups. The DBBM in both groups was covered with NBCM in a double-layered fashion. A crossed horizontal mattress suture (hidden X) was then made. A core biopsy was performed using a trephine bur without flap elevation at the implant placement site for histomorphometric evaluations after 4 months. The change of the marginal bone level was measured using radiography. Results: Twelve patients completed the study. The histomorphometric analysis demonstrated that the mean ratios of the areas of new bone, residual graft material, and soft tissue and the implant stability quotient did not differ significantly between the groups (P>0.05). However, the mean size of the residual graft material showed a significant intergroup difference (P<0.05). Conclusions: The application of 2 compressive forces (5 N, 30 N) on particulate DBBM grafts during open-healing ARP in the posterior area led to comparable new bone formation, implant feasibility and peri-implant bone level.

내부고객 지원활동이 종업원의 시장지향성과 고객지향성에 미치는 영향에 관한 연구 (A study on the Effects of Internal Customer Assistance Activity on Market Orientation and Customer Orientation)

  • 이근홍;장병집;윤지은;김용범
    • 대한안전경영과학회지
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    • 제14권3호
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    • pp.245-257
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    • 2012
  • Business environment, competition among firms in recent years, diverse and fragmented by the symbol of the consumer has become very complex and intense. Nevertheless, for the best performance of firms differentiated their company strives to have unique core competencies. In this study, reviewing the internal customer support activities and existing research on market orientation and then how it affects the future strategy for the internal customer support activities. Through the results of this study, first, to appear understanding of the effect of education and training to customers in enterprise-wide, strategic plan through competitor analysis, improved communication between departments, etc need to design to be effective in performance of company in a long term when in planning and training for employees such as job training, service training and training for improving service mind. Second, employment stability and internal communications to the employee's customer orientation showed no significant affect. This is considered for employees due to lack of fear or anxiety, so the employer could focus on his role in the current organization willing to participate actively for goals of the organization. Finally external customer orientation in the employee's customer orientation did not affect the analysis results which is appeared to in companies are constantly communicating with employees through the company's position and the difference between the employee's position is necessary to look for ways to narrow down.

Estimation of the zone of excavation disturbance around tunnels, using resistivity and acoustic tomography

  • Suzuki Koichi;Nakata Eiji;Minami Masayuki;Hibino Etsuhisa;Tani Tomonori;Sakakibara Jyunichi;Yamada Naouki
    • 지구물리와물리탐사
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    • 제7권1호
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    • pp.62-69
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    • 2004
  • The objective of this study is to estimate the distribution of a zone disturbed by excavation (EDZ) around tunnels that have been excavated at about 500 m depth in pre-Tertiary hard sedimentary rock. One of the most important tasks is to evaluate changes in the dynamic stability and permeability of the rock around the tunnels, by investigating the properties of the rock after the excavation. We performed resistivity and acoustic tomography using two boreholes, 5 m in length, drilled horizontally from the wall of a tunnel in pre-Tertiary hard conglomerate. By these methods, we detected a low-resistivity and low-velocity zone 1 m in thickness around the wall of the tunnel. The resulting profiles were verified by permeability and evaporation tests performed at the same boreholes. This anomalous zone matched a high-permeability zone caused by open fractures. Next, we performed resistivity monitoring along annular survey lines in a tunnel excavated in pre-Tertiary hard shale by a tunnel-boring machine (TBM). We detected anomalous zones in 2D resistivity profiles surrounding the tunnel. A low-resistivity zone 1 m in thickness was detected around the tunnel when one year had passed after the excavation. However, two years later, the resistivity around the tunnel had increased in a portion, about 30 cm in thickness, of this zone. To investigate this change, we studied the relationship between groundwater flow from the surroundings and evaporation from the wall around the tunnel. These features were verified by the relationship between the resistivity and porosity of rocks obtained by laboratory tests on core samples. Furthermore, the profiles matched well with highly permeable zones detected by permeability and evaporation tests at a horizontal borehole drilled near the survey line. We conclude that the anomalous zones in these profiles indicate the EDZ around the tunnel.

IRRADIATION PERFORMANCE OF U-Mo MONOLITHIC FUEL

  • Meyer, M.K.;Gan, J.;Jue, J.F.;Keiser, D.D.;Perez, E.;Robinson, A.;Wachs, D.M.;Woolstenhulme, N.;Hofman, G.L.;Kim, Y.S.
    • Nuclear Engineering and Technology
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    • 제46권2호
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    • pp.169-182
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    • 2014
  • High-performance research reactors require fuel that operates at high specific power to high fission density, but at relatively low temperatures. Research reactor fuels are designed for efficient heat rejection, and are composed of assemblies of thin-plates clad in aluminum alloy. The development of low-enriched fuels to replace high-enriched fuels for these reactors requires a substantially increased uranium density in the fuel to offset the decrease in enrichment. Very few fuel phases have been identified that have the required combination of very-high uranium density and stable fuel behavior at high burnup. U-Mo alloys represent the best known tradeoff in these properties. Testing of aluminum matrix U-Mo aluminum matrix dispersion fuel revealed a pattern of breakaway swelling behavior at intermediate burnup, related to the formation of a molybdenum stabilized high aluminum intermetallic phase that forms during irradiation. In the case of monolithic fuel, this issue was addressed by eliminating, as much as possible, the interfacial area between U-Mo and aluminum. Based on scoping irradiation test data, a fuel plate system composed of solid U-10Mo fuel meat, a zirconium diffusion barrier, and Al6061 cladding was selected for development. Developmental testing of this fuel system indicates that it meets core criteria for fuel qualification, including stable and predictable swelling behavior, mechanical integrity to high burnup, and geometric stability. In addition, the fuel exhibits robust behavior during power-cooling mismatch events under irradiation at high power.

국내외 물류산업의 사물인터넷(IoT) 현황과 발전방향에 관한 연구 (A Study on Logistics Distribution Industry's IoT Situation and Development Direction)

  • 박영태
    • 경영과정보연구
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    • 제34권3호
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    • pp.141-160
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    • 2015
  • USNs, NFC, M2M에서 확장된 사물인터넷은 새로운 컨버전스 기술로써 주요 이슈가 되고 있다. 사물인터넷은 인간의 개입 없이 센싱 네트워크와 프로세싱 간에 공동으로 지능형 연결을 구축할 수 있는 네트워킹으로 정의된다. 본 연구의 목적은 사물인터넷이 물류 산업에 기여하는 것과 미래 사회에 대한 변화를 예측하는 것이다. 실제 세계 시장의 리더가 되기 위해서는 물류 산업의 사물인터넷 개발을 더 많이 요구하고 새로운 서비스 창조와 차별화된 시장을 위한 전략이 필요하다. 그러므로 물류 산업의 세계 리더가 되기 위해서는 다른 것들 보다 사물인터넷 표준화, 사생활 보호, 보안문제 등이 중요하다는 것을 알 수 있다. 따라서, 본 연구에서는 물류 산업의 사물인터넷 개발을 위해서 고객편의를 높이도록 노력하고 소비자의 수요를 잘 고려하여 차별화된 사물인터넷 물류 서비스를 제공할 수 있게 하여야 한다는 것을 보여주고자 함이 본 논문의 목적이며, 이를 위해 국내외 사례를 분석하고자 한다.

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Stabilization of Quinonoid Intermediate E-Q by Glu32 of D-Amino Acid Transaminase

  • Ro Hyeon-Su;Jeon Che-Ok;Kim Hak-Sung;Sung Moon-Hee
    • Journal of Microbiology and Biotechnology
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    • 제16권9호
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    • pp.1434-1440
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    • 2006
  • The stable anchorage of pyridoxal 5'-phosphate (PLP) in the active site of D-amino acid transaminase (D-AT) is crucial for the enzyme catalysis. The three-dimensional structure of D-AT revealed that Glu32 is one of the active site groups that may playa role in PLP binding. To prove the role of Glu32 in PLP stability, we firstly checked the rate of the potential rate-limiting step. The kinetic analysis showed that the rate of the ${\alpha}$-deprotonation step reduced to 26-folds in E32A mutant enzyme. Spectral analyses of the reaction of D-AT with D-serine revealed that the E32A mutant enzyme failed to stabilize the key enzyme-substrate intermediate, namely a quinonoid intermediate (E-Q). Finally, analysis of circular dichroism (CD) on the wild-type and E32A mutant enzymes showed that the optical activity of PLP in the enzyme active site was lost by the removal of the carboxylic group, proving that Glu32 is indeed involved in the cofactor anchorage. The results suggested that the electrostatic interaction network through the groups from PLP, Glu32, His47, and Arg50, which was observed from the three-dimensional structure of the enzyme, plays a crucial role in the stable anchorage of the cofactor to give necessary torsion to the plane of the cofactor-substrate complex.